Siyensikula TIME DILATION: THE TWIN PARADOX_National Science and Technology Fair (NSTF) 2021

Summary

In this fascinating exploration of the twin paradox, identical twins Jack and Joe undergo a unique test of time. While Jack remains on Earth, Joe embarks on a 30-year space mission at 99% the speed of light. Upon reunion, Jack is 60, but Joe, experiencing time dilation due to Einstein's Special Theory of Relativity, is only 34. The Lorentz factor, which multiplies by seven at such speeds, illustrates how time dilates for the moving twin. This phenomenon also underpins GPS technology, proving that the faster an object moves, the slower time passes relative to a stationary observer.

Takeaways

• 👯 Joe and Jack are identical twins, but Joe went on a space mission while Jack stayed on Earth.
• 🚀 Joe's spaceship traveled at 99% of the speed of light, taking 15 years to reach the destination and 15 years to return.
• ⏳ When Joe returns to Earth, Jack is 60 years old, but Joe is only 34 years old due to the effects of time dilation.
• 🧠 Einstein's Special Theory of Relativity explains this time difference, stating that the faster an object moves through space, the slower it moves through time.
• 🔢 The Lorentz factor quantifies this relationship; at 99% of the speed of light, time passes seven times slower for Joe than for Jack.
• 🕰️ During Joe's journey, all his time-based processes, including biological clocks, slow down, making him age more slowly.
• 🌍 The concept of time dilation explains the apparent 'paradox' that Joe perceives Jack's time passing more slowly, but Jack ages faster.
• 📡 Time dilation also underlies the functioning of the Global Positioning System (GPS).
• 📚 The 'Twin Paradox' isn't truly a paradox; it is resolved by understanding different reference frames in relativity.
• 🔍 The closer an object moves to the speed of light or the stronger the gravitational field, the more significantly time passes differently for that object.

Q & A

What is the mystery regarding the twins' ages after one returns from space?

The mystery is that after one of the twins, Joe, returns from a 30-year space mission traveling at 99% the speed of light, he is significantly younger than his twin, Jack, who remained on Earth.

Why does Joe, the twin who traveled through space, age slower than Jack?

Joe ages slower due to Einstein's Special Theory of Relativity, which states that the faster an object moves through space, the slower it moves through time.

What is the Lorentz factor and how does it relate to time dilation?

The Lorentz factor is a mathematical expression that quantifies the degree of time dilation experienced by an object moving at a significant fraction of the speed of light. It is derived from the Special Theory of Relativity.

What is the Lorentz factor at 99% the speed of light?

At 99% the speed of light, the Lorentz factor is seven, meaning time passes seven times slower for Joe on the spaceship compared to Jack on Earth.

How does the concept of a reference frame solve the twin paradox?

The concept of a reference frame in physics allows us to understand that the so-called twin paradox is not a paradox at all. Each twin has a different frame of reference, leading to different experiences of time.

How does the speed of light affect the rate of aging?

The closer an object gets to the speed of light, the slower its biological processes, including aging, occur compared to an object at rest or moving more slowly.

What is the significance of time dilation in the global positioning system?

Time dilation is crucial for the accuracy of the global positioning system (GPS), as it accounts for the difference in time experienced by satellites moving at high speeds relative to Earth.

What happens to Joe's biological clocks during his journey at near-light speed?

Joe's biological clocks, including his brain, heart, and lungs, slow down during his journey at near-light speed, resulting in a slower rate of aging.

Why doesn't Joe notice the time slowing down during his space travel?

Joe does not notice time slowing down because all time-based processes, including his perception and biological functions, decelerate in sync with his speed.

How old are Jack and Joe after Joe's return from space?

After Joe's return from space, Jack is 60 years old, while Joe is only 34 years old, demonstrating the effect of time dilation on their aging.

What is the role of gravity in the perception of time?

The greater the gravitational field, the more time passes differently for an observer in that field compared to one who is not experiencing the same gravitational force.